Next-Gen Prius: What Will a Little Sunshine Get You?

Automaker Toyota will include solar panels on some of its new cars, according to reports in Japan’s Nikkei newspaper. Toyota will add the energy-catching panels to the roof of its hybrid Prius as soon as Spring 2009.

The panels would reportedly be used to power the Prius’ electronics — specifically the air conditioning system, which would need two to five kilowatts of energy to run. Details are few, but Toyota plans to deliver a third-generation redesigned Prius next year.

The Prius is a gasoline/electric hybrid that captures the kinetic energy normally lost during braking, as well as using its gasoline engine, to charge its battery. The Prius then runs on electric power whenever it’s most efficient to do so.

Avoiding the Pump

Automakers around the world are racing to produce vehicles that can beat rising gasoline costs. However, despite the promise of using electricity for vehicle drivetrains, solar panels are a long way from completely powering a car’s engine. Even if a driver could avoid rain clouds and count on plenty of sunshine, the surface area of a typical car — or Prius, for that matter — isn’t able to harness enough energy from the sun to propel the Prius.

“Car rooftop panels can provide only enough energy for vehicle cooling while parked, maybe a small contribution while driving,” Felix Kramer, founder of CalCars, told TechNewsWorld. CalCars is a nonprofit organization that promotes plug-in hybrid electric vehicles (PHEVs).

“This story will get lots of attention and will give people the impression Toyota is doing something pioneering, unique and valuable. We wish Toyota would instead focus on rapid progression to PHEVs. By far the largest leap comes from adding a larger battery and grid-charging so the vehicle can have an energy source besides gasoline,” Kramer explained. For the foreseeable future, he noted, solar cells belong on buildings, including garages, where they can be made larger. Also the auto-related issues of durability and aerodynamics are not a big challenge when solar panels are built into a standing structure.

Selling Fast

Worldwide, Toyota reports that it has sold well over a million Prius vehicles, and more than 591,000 have been sold in North America. The company estimates that Prius hybrids have contributed to a reduction in greenhouse gas emissions of approximately 4.5 million tons of CO2 compared to non-hybrid, gasoline-powered vehicles in the same class and of similar size and driving performance.

The 1.5 L 4-cylinder, four-door Prius Hybrid gets up to 48 miles per gallon, making it — according to the United States Environmental Protection Agency (EPA) — the most fuel-efficient car sold in the U.S.

Mazda briefly manufactured a sedan — the Eunos 800 — in the 1990s that sported a solar panel that was used to charge the battery and remove hot air from the interior during hot sunny days; however, the vehicles never really took off in sales.


  • This is purely a comfort item.

    Ever get into your car on a hot, sunny day? It can be very hot, much hotter than the outside air.

    The solar cells power a fan that circulates outside air though the car. It is not NEARLY big enough to run the AC, though the AC is electric, starting with the US Generation Two car (the first hatchback).

  • ANY steps are welcome, toward our use of solar or other such non burning fuels in our transportation. A first step was taken when this company came up with the present configuration. We should encourage them but supporting what they have done, and in the meantime continue to ask (demand politely) more. Air conditioning DOES use gasoline, as in present automobile systems. The motor must run to provide the pumps, etc. Hey – even if the darn panels only helped with powering the radio and sound equipment, that would be better than what we have now. Bow if we could just add a wind cylinder to push it!

  • I don’t think this idea is bad at all! I have a prius and when I AM using the ac I go from averaging 50mpg (in city) to 40mpg. If solar panels are only enough to add a little extra oomph (10mpg extra)than that is okay by me!

    Actually, my husband and I were talking about this all-or-nothing attitude people have towards green ideas. It is very defeatist and does nothing towards getting new and innovative ideas that can be fine-tuned and expanded upon in the mainstream. Everyone poo-pooed the prius originally and now it is one of the most popular cars on the market and has helped spur other car manufacturers to jump on the band wagon.

  • D’oh! – Where do you think the power from the solar panels will go? To the whole car! so, this will not just feed the A/C, radio, or whatever, but bring some (small, yes, but still some) MPG savings! Also, when the car is parked all day, here in California, the panels will NOT be turned off! They will charge the BATTERIES! Yes, now, the batteries are small, but at least this ensures full batteries when you start.

    Plug-in is great too! When the batteries are full, the plugged car can feed the excess power to the grid.

    But I don’t think that this is what Big Energy wants to hear. Solar panels mean we need less power plants, less oil, less nuchelar.

  • obviously this idea is rather small potatoes, but what i’d like to know is more about plug in hybrids.

    they seem like such a popular idea, surely someone can tell me how much it would tack onto your monthly powerbill to charge a car battery every night, and also the carbon emissions that would entail, since the majority of power in the united states still comes from coal I believe.

  • This seems like the equivalent of ripping the solar cells out of my solar-powered calculator and trying to run my 400 watt computer or even possibly a Spinal Tap Concert! It might help power, say, the LED "on" light, but it’s pretty much not worth it.

    I’m totally an environ-mental, but I have to say that this is a ridiculous idea. …Having a large solar grid that charges a plug-in hybrid? =Brilliant idea. Toyota is banking on people’s ignorance of energy and I find it insulting. Get on with the Plug-ins already!!!

  • The Aptera ( is already using solar panels this way while also addressing issues with aerodynamics and they have both a full electric and hybrid electric model in the works. Add to this that they are also getting much better gas mileage (on the hybrid) and it comes out a clear winner. The only thing that they are lacking that the Prius has is the extra passenger room.

    It is great to see Toyota taking this step, I wish they would go the extra step of incorporating a plug-in option and improving fuel economy, but this is a good step to see one of the major auto-makers taking. Hopefully further advancements will be coming out more quickly.

Leave a Comment

Please sign in to post or reply to a comment. New users create a free account.

Technewsworld Channels